Cardiovascular disease is the leading cause of death in the U.S. today and has been so for the last century. Approximately 70 million Americans suffer from some form of cardiovascular disease and many require ongoing pharmacological therapy. Mississippi has the highest annual age-adjusted death rate from cardiovascular disease of any state in the U.S. Known risk factors for cardiovascular disease probably account for much of this disparity but other factors may be playing a role. Increasingly, the role of environmental toxicants in cardiovascular disease is being recognized. Mississippi has an agricultural based economy and much of the population resides in rural settings close to where crops are grown. This proximity results in the contact of the population with current use pesticides as well as legacy pesticides, those pesticides used in the past but persistent in the environment today. Recent studies have shown exposure to chlorpyrifos, an organophosphate insecticide, in utero can affect the adenylyl cyclase signaling pathway in cardiac myocytes. However, little is known about the effect of pesticides on the development, progression, and pharmacological treatment of cardiovascular disease. This grant proposes to examine the effects of two environmentally relevant pesticides, dieldrin and chlorpyrifos, on the rat cardiac proteome. Dieldrin is a legacy pesticide used extensively in the 1950's and 1960's (though currently banned in the U.S.) which is still present in soil samples from the Mississippi Delta region. Chlorpyrifos is a pesticide in current use. The goal of this grant is to identify proteins whose levels of transcription and/or post-translational modifications are altered by exposure to these two pesticides. The proteins thus identified will serve to direct further studies aimed at identifying the mechanism of toxicity of these pesticides. Our long-term objective is to better understand the extent to which commonly used pesticides and other environmental chemicals influence heart disease and its treatment. [unreadable] [unreadable] [unreadable]